Sony VFET Amplifier Part 2

[henryve]

Any Idea if a new batch of these would ever be released again?
Thanks

I don't think there will be a new batch of the PP design. There *might* be a project in the pipeline with a SE design using only one (2SJ28) of the VFETs.

 

[Nelson Pass]

If you can point me to another big stash of the Sony complementary
parts, then we could do more.

As it is, we are down to about 500 parts.

 

[kawihornet]

What parts would you require?

 

[WBS]

Sony 2SK82

 

[Dennis Hui]

Hi kawihornet,

There's a Vfet2 kit over at the swap meet:

FS: First Watt Sony VFET 2 Kit – EU

If you're interested, you might want to see if the seller will ship to Canada.

Cheers,
Dennis

 

[Dudeisms]

Hi kawihornet,

There's a Vfet2 kit over at the swap meet:

FS: First Watt Sony VFET 2 Kit – EU

If you're interested, you might want to see if the seller will ship to Canada.

Cheers,
Dennis

Oh if only there was a kit Stateside or in Canada!

 

[rhing]

Oh if only there was a kit Stateside or in Canada!

If I knew the seller, his price with VAT and shipping is worth spending. This amp is fantastic and one of the best I’ve heard in my system.

 

[kawihornet]

Hi kawihornet,

There's a Vfet2 kit over at the swap meet:

FS: First Watt Sony VFET 2 Kit – EU

If you're interested, you might want to see if the seller will ship to Canada.

Cheers,
Dennis

Thanks Dennis!

 

[arky]

+/-35v rails voltage is really too much or (hoping) more or less OK? Having the overheating protection in place (>75'C). As mains AC today goes up to 230V instead of usual 220, that gave 27V AC on secondaries, so rectified and loaded gave 35V. Hate to disassemble the trafo, removing turns etc...

 

[Blk Dynamite]

Anyone know if the store will have the VFET heatsinks available again? I was hoping they would have a small run pending the release of the new kit but since that looks to be on hold for a long while I may have to build the last kit with the boards available on at the store

 

[Nelson Pass]

The new kit has 4 TO-3 devices on the bar. You would need a new pcb
to accommodate that.

 

[Zen Mod]

badaddddddam

two VFets in parallel

adjacent two oldie mosfets as load , damn if I know in which arrangement

TL431 can be squeezed between gates , VFet gate being lower than Mosfet gate

Baaaaaad Papa!

 

[Blk Dynamite]

The new kit has 4 TO-3 devices on the bar. You would need a new pcb
to accommodate that.

Ah gothca, thanks! I guess it would have helped if I looked into the thread "What to do with those 2Sj8s" ha

 

[arky]

Ok, now two boards are up and running. R34 and R35 replaced with 333ohm, got 1V voltage drop at R5 and R6, 0.1V at T18 and about zero output. Now have to put them into the chassis and - to listen. Thank ya all for your support!!!

It seems now that the amp is relatively quieter then my other equipment. Apparently I was not able to get 36dB... scope is showing maximum amplitude at the output (circa 40V peak to peak, pure sine wave) while input signal is about 6V peak to peak. So if my math is correct, there's only 20dB or so on voltage. Should I increase R3 say, up to 8-10k?

 

[flocchini]

ZM, Dennis

My VFET2 board looks like an exploded mine field with all the solder/unsolders - may have screwed up a trace and am not seeing it.

Decided to go the path of least resistance
Tea-Bag is sending a new board.

Thanks for your help

Best

Bob

 

[Dennis Hui]

Given the trouble you've had, maybe that's the best thing. Good thing
Teabag is able to supply a pcb.

All the best with your rebuild.

Cheers,
Dennis

 

[flocchini]

Thanks Dennis

 

[kawihornet]

If I'm able to source a pair of Sony 2SK82 is the rest of the kit available? or only as a package? Thanks
Nathan

 

[Nelson Pass]

The parts and boards can be had, even if they have to be gathered individually.

 

[dantwomey]

The new kit has 4 TO-3 devices on the bar. You would need a new pcb
to accommodate that.

Very interesting.... first week of March?

Regards,
Dan